SU1256762A1 - Method of automatic control of heat conditions of condensating and steaming part of methane column - Google Patents

Description

"

The invention relates to methods for automatically controlling the thermal conditions of a methane column and can be used in the petrochemical industry.

The purpose of the invention is to reduce the loss of the target product - ethylene with methane fraction.

The drawing shows a diagram of the implementation of the method.

The circuit includes pressure sensors 1, pressure sensors 2 of the condensation section 3 of the column, sensors 4 of the top temperature, sensors 5 of the supply temperature, sensors 6 of the supply flow in the same apparatus, as well as sensors 7 of the temperature of the top, the control plate 8 and the cube 9 of the Stripping part 10 of the column The signals from which are converted to pneumatic and fed to the throttle adder 11 The output of the throttle adder 11 is connected to the controller 12, the output of which is connected to the actuator 1 3 on the coolant supply line to the reflux condenser 14 and a register 15 with a dead zone. The output of the controller 15 is connected to the software} by the input of the controller 16, n

the input of which receives a signal from the tuning parameters of the executive

The temperature of the product flow from the condensation part of the column to the stripper is 17, and the outlet is connected to the executive mechanism 18 on the coolant supply line to the evaporator 19.

The method is carried out as follows.

The signals from the sensors 1, 2, 4-9 process parameters are fed to the throttle adder 11, where in accordance with the equation the ethylene content in the methane fraction is calculated:

,, + Kg uP +

(one)

K P + Kgli-K, ts,

de С - ethylene content in methano-.

hydrogen fraction; - feed temperature of the methane column;

j, is the temperature of the top of the condensation part; and - the temperature of the top steam

parts;

t is the temperature of the control plate of the stripping part; DR is the pressure drop of the condensation part;

t,

g t.

P is the pressure of the condensation part;

G is the flow rate of the methane column; t is the temperature of the bottom of the steam

columns.

The processing is conducted by the least squares method, the Fisher criterion is 2.32, the table value is 5.385, the coefficient of multiple corruption is 0.919. .

The coefficients of equation (1) have the following meanings: K, 21.2697; K 0.4127; , 5858; , 2224; , 0658; Kg l, 7611; K.0,0123; , 0232; l328o

A signal proportional to the ethylene content is fed to the regulator 12, acting on the executive mechanism 13, installed on the coolant supply line to the reflux condenser 14, when the calculated value of the ethylene content changes from the specified value. The output of the controller for the transistor 12 also goes to the controller 15 with the dead zone, being variable for it. On the controller 15, a dead zone is set, determined by the boundary values

five

0

mechanism 13. If the output from regulator 12 is within these limits, then the output from regulator 15, which is the task of regulator 16, does not change. In this case, the regulator 6 maintains the temperature of the product entering the apparatus 10 at a predetermined level, affecting the executive mechanism: 18, which, together with the operation of the regulator 12, provides a predetermined value of the ethylene content in the methane fraction. I

If the output signal from the regulator 12 goes beyond the limit of the dead zone, it means that the actuator 13 is in one of the extreme positions (closed or completely

0 open), a further change in this signal does not cause a change in the coolant flow rate and, consequently, in the technological mode, the output signal of the controller 15 in this

5 case, the assignment of the regulator 16 to that side in order to change the ethylene content in methane hydrogen by changing the temperature of the product on the overflow

fraction reached a predetermined. After the ethylene content reaches the specified value, the output of the regulator 12 will take some average value, i.e. will be12567624

in the dead zone of the controller 15, and therefore, the output signal of the controller 15 (setting of the controller 16) is stabilized and will be equal to its last value.

Compiled by T. Golenshin Editor M, Tovtin Tehred I. Weres Corrector O. Lugova

Order 4854/3 Circulation 663 Subscription

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Production and printing company, Uzhgorod, st. Project, 4

Claims (1)

METHOD FOR AUTOMATIC REGULATION. HEAT MODE OF THE CONDENSATION AND STEAM PART OF THE METHANIC COLUMN by changing the flow pressure, supply temperature and the top temperature of the condensation part of the column, the temperature of the top, cube and control plate of the stripping part of the column and changing the flow rate of the coolant, characterized in that, in order to reduce the loss of the target product is ethylene with a methane-hydrogen fraction, measure the pressure drop in the condensation part and, depending on the current values of the measured parameters, form a signal proportional to the content of ilene in the methane-hydrogen fraction, and depending on the magnitude of the deviation, regulate the flow of coolant to the reflux condenser, the flow rate of the coolant to the evaporator on _the product flow from the condensation part to the steam is corrected. Depending on the position of the actuator of the control valve on the coolant supply line to the reflux condenser . SU ,,, 1256762